The KDE project saw the writing on the wall. They saw that they had reached a certain limit when it came to what could be done with the KDE 3.x series - they named it the "big friggin' wall", and decided that in order to get over that wall, incremental updates wouldn't do - they needed massive changes, a big jump, and they went for it. It's been a rough road, but it seems as if KDE 4.1 is showing signs of the vision becoming a reality. And it now seems as if several people within the GNOME community are seeing the writing on the wall too: GNOME 2.x has reached its goal - now what?